D. Beitz - Academia.edu (original) (raw)

Papers by D. Beitz

Endocrinology, 1994

We have reported that PTH inhibits 25-hydroxyvitamin D3-24-hydroxylase messenger RNA (mRNA) expre... more We have reported that PTH inhibits 25-hydroxyvitamin D3-24-hydroxylase messenger RNA (mRNA) expression induced by 1 alpha,25-dihydroxyvitamin D3 [1 alpha, 25-(OH)2D3] in rat kidney but not intestine. In the present study, we examined whether the suppression of 24-hydroxylase mRNA expression by PTH occurs commonly in tissues and cells which have PTH receptors. Administration of 1 alpha, 25-(OH)2D3 into rats fed a synthetic vitamin D-repleted diet containing adequate calcium greatly increased serum levels of calcium and 1 alpha, 25-(OH)2D3. Also, there was a 4-fold increase in bone 24-hydroxylase activity in response to 1 alpha, 25-(OH)2D3 administration. In rats fed a low calcium diet, renal 24-hydroxylase activity was suppressed probably due to secondary hyperparathyroidism. In contrast, the low calcium feeding did not suppress bone 24-hydroxylase activity. The expression of 24-hydroxylase mRNA in rat osteoblastic C-26 and C-11 cells was similar and attained maximal levels 24 h after cells were incubated with 10(-8) M 1 alpha, 25-(OH)2D3. Induction of 24-hydroxylase mRNA expression by 1 alpha, 25-(OH)2D3 was much greater and earlier in immature C-26 cells than mature C-11 cells. Simultaneous addition of PTH, prostaglandin E2, or cAMP together with 1 alpha, 25-(OH)2D3 did not down-regulate mRNA expression of 24-hydroxylase induced by the vitamin in both C-26 and C-11 cells. Of the three osteoblastic cells (C-26, C-20, and C-11) examined, C-26 cells showed the least mRNA expression of vitamin D receptors, in spite of the highest expression of 24-hydroxylase mRNA. These results suggest that unlike in the kidney, bone 24-hydroxylase mRNA expression is not down-regulated by PTH despite of the presence of PTH receptors. They also suggest that the degree of the induction of 24-hydroxylase mRNA by 1 alpha, 25-(OH)2D3 is not explained simply by the vitamin D receptors content.

Journal of Animal Science, 2007

Additional file 8: Supplemental Data. Differential expression results based on UMI data for the t... more Additional file 8: Supplemental Data. Differential expression results based on UMI data for the treatment groups versus control obtained from Qiaseq Secondary analysis pipeline.

Additional file 5: Supplemental Table 5. Detailed results from statistical testing of total miRNA... more Additional file 5: Supplemental Table 5. Detailed results from statistical testing of total miRNA abundance levels using DESeq2 in different milk samples against the raw whole milk as the control group.

Additional file 2: Supplemental Table 2. Gene ontology (GO) IDs over-represented in list of gene ... more Additional file 2: Supplemental Table 2. Gene ontology (GO) IDs over-represented in list of gene targets (specific to B. taurus) for which miRNAs have been found in the milk samples.

The Journal of Nutrition, 1975

Controls of fatty acid synthesis in bovine adipose tissue were investigated. Six Brown Swiss stee... more Controls of fatty acid synthesis in bovine adipose tissue were investigated. Six Brown Swiss steers were fasted for 8 days and then refed for 56 days. Biopsy samples of backfat adipose tissue were taken during the fasting and refeeding periods. Rates of acetate incorporation into fatty acids (FAS), activities of acetyl CoA carboxylase (CBX), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and NADP:isocitrate dehydrogenase, and plasma free fatty acids (FFA) and plasma acetate were determined. FAS decreased 60% after 1 day of fasting and 99% after 8 days. FAS did not increase until day 3 of refeeding when energy intake was above maintenance, then returned to normal by 14 days. CBX followed a pattern similar to FAS, except its activity did rise above the control rate during refeeding. Plasma FFA increased 350% and acetate decreased 67% during fasting. After 4 days of refeeding, FFA returned to normal, and acetate increased to 156% of initial concentration, then returned to normal by 21 days. These data suggest that CBX limits FAS in adipose tissue of cattle.

Journal of Animal Science, 2002

Journal of Dairy Science, 1999

Hepatic cholesterol 7α-hydroxylase (CYP7A) and sterol 27 hydroxylase activities were mea- sured i... more Hepatic cholesterol 7α-hydroxylase (CYP7A) and sterol 27 hydroxylase activities were mea- sured in fetal, newborn, suckling, and weaned piglets from 76 d into gestation to 49 d of age. Hepatic CYP7A activity was not detected in fetal microsomes, but it increased to 6.8 ± 2.6 pmol/minmg−1 protein in suckling piglets at 21 d of age and to 18.2 ± 2.5

International Journal of Systematic Bacteriology, 1994

Journal of Dairy Science, 2015

Journal of Dairy Science, 2007

Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 1989

Journal of dairy science, 2014

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD... more Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD). One mode of transmission of MAP is through ingestion of contaminated milk and colostrum by susceptible calves. The objective of this study was to determine if the amount of MAP shed into the milk and colostrum of infected cows was affected by severity of infection as well as the number of days in milk (DIM). Milk was collected over the 305-d lactation period from naturally infected cows in the asymptomatic subclinical (n=39) and symptomatic clinical (n=29) stages of disease, as well as 8 noninfected control cows. All milk samples were assayed for MAP by culture on Herrold's egg yolk medium and either BACTEC 12B (Becton Dickinson, Franklin Lakes, NJ) or para-JEM (Thermo Fisher Scientific, Trek Diagnostic Systems Inc., Cleveland, OH) liquid medium, and by direct PCR for the IS900 target gene. Mycobacterium avium ssp. paratuberculosis was detected in 3.8, 4.1, and 12.6% of milk sampl...

Laboratory animal science, 1991

Techniques were developed in young growing pigs to simultaneously collect and reinfuse bile. Sila... more Techniques were developed in young growing pigs to simultaneously collect and reinfuse bile. Silastic cannulae were designed and surgically implanted in the common bile duct and the duodenum. Direct sampling of the hepatic bile was achieved by bypassing the gallbladder. The techniques allowed for steady-state studies of hepatic function to be conducted in conscious swine in two different studies. Pigs, thus surgically modified, can serve as an appropriate model for physiologic, pharmacologic, and nutritional research that involves bile sampling.

Journal of dairy science, Jan 19, 2015

Feeding lactating dairy cows dried distillers grains with solubles (DDGS) increases the concentra... more Feeding lactating dairy cows dried distillers grains with solubles (DDGS) increases the concentration of unsaturated fatty acids in the milk from those cows, potentially leading to increased susceptibility to development of off-flavors. Feeding DDGS has been loosely implicated to be a cause of development of spontaneous oxidative off-flavor in milk. We hypothesized that increased feeding of DDGS would accelerate development of off-flavors and that fortification with vitamin E (0.06% wt/wt) or C (0.06% wt/wt) would prevent spontaneous oxidative off-flavors. The objective of this research was to determine the effects of feeding DDGS to lactating dairy cows on several parameters of milk quality as determined by both chemical and sensory evaluations. Twenty-four healthy mid-lactation Holstein dairy cows were fed total mixed rations containing DDGS (0, 10, or 25% dry matter). Cows were blocked by parity and randomly assigned to 1 of 2 groups (12 cows each). Each group received all 3 trea...

Journal of Dairy Science, 1991

Veterinary Immunology and Immunopathology, 1996

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the biologically active metabolite of vitamin D, and delt... more 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the biologically active metabolite of vitamin D, and delta 22-26-F3-1,25-dihydroxyvitamin D3 (delta 22-26-F3-1,25(OH)2D3), a synthetic analog with a high affinity for the vitamin D receptor, significantly inhibited interferon-gamma (IFN-gamma) secretion in 24- and 48-h cultures of pokeweed mitogen (PWM) and ovalbumin (OVA) stimulated peripheral blood mononuclear leukocyte (MNL) from adult, OVA-sensitized dairy cattle. Vitamin D-induced inhibition of IFN-gamma production was most pronounced in MNL cultures supplemented with 1,25(OH)2D3 at 1.0 nM or more, a concentration equal to or exceeding that in plasma of cows with clinical hypocalcemia. Secreted IFN-gamma was undetectable in all resting MNL cultures. Ultra-low concentrations (0.0001, 0.001, and 0.01 nM) of 1,25(OH)2D3 had no effect on IFN-gamma secretion by PWM-stimulated bovine MNL, unlike a previous study in other species demonstrating enhancement of IFN-gamma secretion at these concentrations. Preincubation of MNL with.